bridge



Feb. 3, 1931'. E. H. BRIDGE I 3 5 I IYDROME-TER SYRINGE Filed May 10, 1929 k m mwm/e I Patented-Feb: 3, 1931 UNITED STATES PA-TENT OFFICE ELLIS H. BRIDGE, OF AKRON, OHIO, ASSIGNOR TO THE ELECTRIC STORAGE BATTERY COMPANY, OF PHILADELPHIA, PENNSYLVANIA, A CORPORATION 01 JERSEY nYDRomETEB. SYRINGE Application filed May -10,

My invention relates to hydrometer syringes particularly those adapted for usew th storage batteries or for measuring the specrfic gravity of the cooling fluidof-automoblle or other internal combustion engines.

The object of this invention is to produce an improved hydrometer syringe in which.

. the liquid does not comeinto contact with the portions of the barrel of the hydrometer through which the readings are made so that these portions do not become obscured and therefore readings may be more accurately made.

A still further feature of my invention is that in my hydrometer the'indicatmg markings may be located on the barrel of the hydrometer thus enabling a more accurate reading to be made then when the markings are on the float as has heretofore been the common practice.

An additional feature of my'invention i's an hydrometer in which the bulb is in liquid contact with the liquid whose specific gravity is being measured so that if the operator of the hydrometer retains manual hold'on the bulb thevibrations .or tremors of his hand- I will not cause vibrations 0r fluctuations of 192e. Serial No. 361,861.

of my invention will out and claimed.

In the drawings,

be specifically pointed Figure 1 represents a view partially in cross-section through my device.

Figure 2 is a cross-section showing a modified form of my device;

In the drawings there is shown an hydrometer syringe consisting of a hollow tubular barrel or casing 1 having a neck 2 of reduced diameter extending therefrom. At the end of the neck 2 there may advantageously be located a flexible filling tube 3.

At the opposite end of the barrel 1 there is located a ulhA: of; flexible material. Be-

tween the bulb 4 and the barrel 1 there is 10- cated a stopper or plug 5 which serves to seal the barrel 1 from the bulb 4. Extending through the stopper 5 and down into the barrel 1 is a tube 6 which may advantageously f be made of hard rubber or other suitable materiall', Preferably, this tube is-shaped so as barrel 1 which may be composed, wholly or r in part, of transparent or translucent materia The operation of my device is as follows: When it is desired to ascertain the specific gravity of a body of liquid the flexible tube 3 is inserted into the liquid and the bulb 4 squeezed or pressed upon so as to be contracted. The bulb 4 is then allowed to expand and fluid is drawn up into the barrel 1. A sufficient amount of liquid is drawn up into the barrel 1 until tube 6 contacts with the surface of the liquid. The suction of the bulb 4 then serves to draw the liquid through the tube 6 up into theinterior of the bulb. The upper part of the casing 1 therefore does not come into contact with the liquid so that this surface is not obscured thereby nor do deposits of dirt form on the casing above the fixed level. It is desirable that this surface be kept as clean as possible and thatthe usually clouded liquid should not obscure the stem 7 of the float if the indicating marks are located on the stem of the float. It is neces-,

sary to look through this portion of the casing in order-to view the indicating marks.

If the indicating marks are located on the casing 1 it is, nevertheless, necessaryto look 10 "through'this surface to locate the position of the-top of thefloat. v

f The tube'6 extends into theicasing 1 asuflicient length sothatthe level predetermined for the liquid in the casing 1 is sulficiently low to allow free operation of the float in the casing. In other words, no mat- :;ter how much ofv the stem 8 extends above the surface of the liquid itwill not come into contact with the upper portion of the casing 1 or with the stopper 5. For this reason also it is desirable to locate the tube 6 adjacent to the side of the casing 1 so that it will not interfere with the operation of thefloat 7.

Figure 2 shows a modified form of my device in which the bulb 4 is attached to thebarrel 1 just above the neck 2. It will be apparent that when the bulb 4 of this modification is contracted and allowed to expand the liquid will enter the barrel 1 and 'thenenter the bulb 4, thus establishing a constant levelnear the bottom of the casing 1.

The described device produces a constant level in the liquid chamber and the only variation in respect to variation in density is the i 85" height of the hydrometer float in respect to thecbarrel so that it is possible to mark specific gravity readings directly upon the barrel, as indicated in Fig. 1, and to use the top of the hydrometerifloat as the indicator with respect to the marking on the barrel.

vIclaim 1. An hydrometer syringe for visual indication of specific gravity comprising atransparent barrel having an inlet at one end into which a liquid may be drawn and having an opening at the other end, a float in the barrel,

an elastic bulb mounted on said other end of the barrel, a perforated stopper in said openingat said other end of the barrel, and

a tube communicating with the interior of the bulb through the stopper and extending .into ,the barrel'a suificient distance'so as to draw liquid into the barrel to a fixed level, liquid in excess of that required to fill the barrel to said level'being drawn up into the tube, said float being adapted to be freely suspended in the barrel when the liquid is at said fixed level.

2. An hydrometer syringe for 'th'e'visua indication of specific gravity comprising a transparent barrel, a float located in the barrel and visible through the barrel, said barrel having an inlet through which a liquid A may be drawn into the barrel, and suction V means associated with the barrel, said sucdraw liquid into the barrel to a fixed level tion means having an inlet located at a point intermediate the ends of the barrel so that the suction means will draw-liquid into the barrel to a fixed level at saidpoint and liquid in excess of. that required to fill the barrel to said level will be drawn into the suction means, said float being adapted to be freely suspended in the barrel when the liquid is at saidfixed level.

3. An hydrometer-syringe for the visual indication of specific gravity'comprising a transparent barrel, a float located in the barrel and visible through the barrel, said barrel having an inlet through which a liquid may be drawn into the barrel, and suction means including an elastic bulb associated with the barrel, said suction means having an inlet located at a'p'oint intermediatethe endsof the barrel so that the suction 'meansvwill at said point and liquid in excess of that required to fill the barrel to said level will be drawn into the suction means, saidfioat being adaptedtobe-freely suspended in the barrel when the liquid is at said fixed level.

4. An hydrometer syringe for the visual indication of specific gravity comprising a transparent barrel, a float located in the barrel and visible through the barrel, said barrel having an inlet through which a liquid may be drawn into the barrel, and suction means associated'with the barrel, said suction means having an inlet located at a point intermediate the ends of the barrel'sothat" the suction means will draw liquid into the h barrel to a fixed level at said point and liquid in excess of that required to fill the barrel to said level will be drawn into, the suction said indicia. 11

- ELLIS H. BRIDGE. 

